Greetings monks,

Is it possible to create programs that use IPC to communicate and use the COW (copy on write) functionality on Linux OS?

I'm asking that because I've doing some tests and I could not get an situation that my forked child did not copy all variables from parent process.

I checked this situation by running htop program and seeing that the child process have the same amount of memory than the parent process. For what I have read about COW, the child process will copy its parent process variables in its own address space only if it tries to change those variables. My conclusion is, COW should help to reduce memory consumption but I never could checked that.

Given this little introduction, how can I:

  1. Check if COW is being used (or not) in a Linux box: there is any OS or Perl resource to check that?
  2. In practical terms, is it possible to avoid COW in Perl?

Thank you,

Alceu Rodrigues de Freitas Junior
---------------------------------
"You have enemies? Good. That means you've stood up for something, sometime in your life." - Sir Winston Churchill

In reply to Is it possible to use IPC COW with Perl? by glasswalk3r

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